It may well be that Professor Calvel's book LeGout de Pain
answers the types of questions you raise but I have not been able to find anything that correlates autolyse rest time with flour (or dough) quantity. I have seen recommendations from 5 minutes (for a single dough ball) to 45 minutes, with most of the recommendations being in the 20-25 minute range, without regard to dough batch size. I have read that the chemical activity in a large dough batch is faster than in a small dough batch--a concept known in baking as the mass effect
--so this implies that the autolyse process should take place faster in a large dough batch than in a small dough batch. That may be why the autolyse rest period tends to cap and possibly level off at some point. This is a topic that was discussed a while back at Replies at 489 and 490 at http://www.pizzamaking.com/forum/index.php/topic,576.msg30141.html#msg30141
In your case, I would say that 25 minutes is reasonable for 10 cups of flour and whatever the final dough batch weight is when you add the water and remaining ingredients. Dividing the flour as you indicated should not pose a problem in my opinion.